<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
    <script src="../react18/react-dom.development.js"></script>
    <script src="../react18/babel.min.js"></script>
</head>
<body>
    <div id="app"></div>
    <script type="text/babel">
        class App extends React.Component{
            state ={
                count:0,
            };
            render(){
                return <div>
                    
                    <h1>计算器的值是:{this.state.count}</h1>
                    <button onClick={this.changeCount}>累加</button></div>
            }
            changeCount = ()=>{
                this.setState({
                    count:++this.state.count
                })
            }
        }
        ReactDOM.createRoot(document.getElementById("app")).render(<App />);
    </script>
</body>
</html>